Yes you can rearrange them.
Go to C:Documents and SettingsyourusernamehereApplication DataPoser 7

and open LibraryPrefs.xml with notepad (this location might be different if you are using a mac)

and then select everything from <ContentFolder to and drag it to what ever order you want it.

Keep your Poser 7 and downloads at the top.

And while I don't remember I think you want to change the index numbers to be in order. And of course a back this file up before editing it in case you make a mistake.

Good luck

 edit: sorry you can't drag in notepad, you need to cut and paste

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